Engine control request from adaptive control with braking controller

ABSTRACT

A vehicle control system includes a forward vehicle sensor transmitting a forward vehicle message based on a range to a forward vehicle. An adaptive cruise controller receives the forward vehicle message from the forward vehicle sensor. The adaptive cruise controller transmits a cruise controller message based on the range to the forward vehicle. A braking system controller receives the cruise controller message and transmits an engine control message based on the cruise controller message. An engine controller receives the engine control message and controls a torque and/or speed of an engine as a function of the engine control message.

BACKGROUND

The present invention relates to communication among vehicle controllerson a serial bus. It finds particular application in conjunction withcommunicating engine control instructions among the vehicle controllersand will be described with particular reference thereto. It will beappreciated, however, that the invention is also amenable to otherapplications.

Vehicles, for example heavy vehicles such as trucks and buses,increasingly utilize various controllers on a vehicle data bus (e.g.,SAE 1939) for controlling different functions on the vehicle. In suchconfigurations, each of the controllers includes a specific identifier.Then, a request to increase a torque and/or speed of the vehicle'sengine may be communicated in the form of a message from one of thecontrollers to another one of the controllers via the data bus. Messagestransmitted along the data bus include identifiers of both theoriginating controller and the destination controller. The identifiersare used as the messages are routed along the data bus from theoriginating controller to the destination controller.

It is becoming more common for heavy vehicles to include adaptivecontrol with braking (ACB) systems. ACB systems are used for controllinga speed of a vehicle to maintain a minimum distance behind anothervehicle. Currently, an engine control mode request message (e.g., atorque increase request message or a torque decrease request message)such as a torque/speed control (TSC1) message is transmitted from theACB system to an engine controller. However, since engines of differentmodels and makes have different levels of support for TSC1 messagerequests from an ACB system, only certain engines respond to a TSC1message from an ACB system.

The engine controller may also receive additional control mode requestmessages from other systems on the vehicle. These additional controlmode requests may conflict with the control mode request the enginecontroller receives from the ACB system. The engine controller mayrespond unpredictably upon receiving conflicting control mode requests.

The present invention provides a new and improved apparatus and methodwhich addresses the above-referenced problems.

SUMMARY

In one aspect of the present invention, it is contemplated that avehicle control system includes a forward vehicle sensor transmitting aforward vehicle message based on a range to a forward vehicle. Anadaptive cruise controller receives the forward vehicle message from theforward vehicle sensor. The adaptive cruise controller transmits acruise controller message based on the range to the forward vehicle. Abraking system controller receives the cruise controller message andtransmits an engine control message based on the cruise controllermessage. An engine controller receives the engine control message andcontrols an engine as a function of the engine control message.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings which are incorporated in and constitute apart of the specification, embodiments of the invention are illustrated,which, together with a general description of the invention given above,and the detailed description given below, serve to exemplify theembodiments of this invention.

FIG. 1 illustrates a schematic representation of a vehicle in accordancewith one embodiment of an apparatus illustrating principles of thepresent invention;

FIG. 2 illustrates a schematic representation of a vehicle communicationsystem in accordance with one embodiment of an apparatus illustratingprinciples of the present invention; and

FIG. 3 is an exemplary methodology of transmitting an engine controlrequest in accordance with one embodiment illustrating principles of thepresent invention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENT

With reference to FIG. 1, a schematic representation of one embodimentof a system and method for an adaptive control with braking (ACB) cruisecontrol system is illustrated according to one embodiment of the presentinvention. A vehicle 10 (e.g., a tractor of a tractor semi-trailervehicle) includes an engine E coupled to a transmission T via a clutchmechanism C. In one embodiment, the engine E is electronicallycontrolled. Although the vehicle 10 is illustrated as a tractor-trailervehicle, it is to be understood that any vehicle including, for example,an electronically controlled engine is contemplated.

The vehicle 10 includes at least two axles (e.g., a steer axle 16 and atleast one drive axle, such as axles 18, 20). Each axle supportscorresponding wheels W having foundation or service brake components 22,which may be manually or automatically actuated depending upon theparticular application and operating conditions. For example, a vehicleequipped with an antilock brake system (ABS) may assume automaticcontrol of braking under appropriate conditions (e.g., when the vehicleis braking and the system detects a sufficient slip differential amongone or more of the wheels). The operation of an ABS system is unaffectedby operation of the present invention since an engine control module(ECM) 24 utilizes a priority system defined by the SAE J1587 standard orthe SAE J1939 standard. In one embodiment, the priority system providesthe ABS system a higher priority than the ACB cruise control system,such that the ACB system need not be aware of ABS operation. Servicebrake components 22 may include wheel speed sensors and electronicallycontrolled pressure valves to effect control of the vehicle brakingsystem.

Vehicle 10 may also include conventional operator controls such asclutch pedal 26 (in some manual systems), an accelerator pedal 28, abrake pedal 30, and an operator interface 32 (e.g., a dashboard controlconsole), which may include any of a number of output devices 34 (e.g.,lights, displays, buzzers, gauges, etc.), and various input devices 36(e.g., switches, push buttons, potentiometers, etc). The vehicle controlsystem includes an electronic control module such as the engine controlmodule (ECM) 24 and an additional electronic control module foreffecting control of transmission T, such as transmission control module(TCM) 40. Of course, engine and transmission control may be combined ina single electronic control module for some applications. The ECM 24 andTCM 40 communicate with a variety of sensors via inputs 42 and withnumerous actuators via outputs 44. Sensors may include a steering anglesensor 46, wheel speed sensors (included in braking components 22), anelectronic accelerator pedal sensor (APS) 50, a brake pedal sensor orswitch 52, a clutch control/sensor 54, an output speed sensor 56, and aforward vehicle sensor 58 which indicates inter-vehicle distance and/orclosing rate, among numerous others. It is contemplated that the forwardvehicle sensor 58 provides distance and closure rate informationrelative to vehicle 10 and at least one forward vehicle 60.

A diagnostics module 62 may be selectively connected to the ECM 24 forcommunicating status messages to facilitate diagnostics, service, andmaintenance of vehicle 10. These messages are also available to othersystem controllers (microprocessors), such as the TCM 40, and includeinformation such as current engine speed and torque, acceleratorposition, road speed, cruise control status, and cruise control setspeed, among many others. Cruise control status includes informationrelative to various cruise control switches, brake pedal switch, andclutch pedal position, among others.

It is contemplated that the ECM 24 communicates with TCM 40 according tothe SAE J1939 standard. The forward vehicle sensor 58 communicates withthe ECM 24 and/or the TCM 40. In one embodiment, the forward vehiclesensor 58 communicates directly with the ECM 24 utilizing the SAE J1939standard. However, it is to be understood that the present inventionrelies on the exchange of control and status information independent ofany particular data path or messaging protocol.

With reference to FIG. 2, a vehicle data bus 64 communicates with aplurality of vehicle controllers. In one embodiment, the data bus 64 iscapable of transmitting messages in various formats between the vehiclecontrollers. For example, the data bus 64 is capable of transmittingmessages formatted according to the SAE J1939 standard and, in addition,messages formatted according to other standards (e.g., proprietarystandards). In one embodiment, messages formatted according to the SAEJ1939 standard are “public” messages, since controllers from manydifferent manufacturers are designed to communicate according to the SAEJ1939 standard. Messages formatted according to proprietary standardsare referred to as “private” messages since, for example, only vehiclecontrollers manufactured by a particular manufacturer may be designed tocommunicate according to a particular proprietary standard.

An ACB controller 66 communicates with the data bus 64 via an ACBcontroller communication port 68. An ABS controller 70 communicates withthe data bus 64 via an ABS controller communication port 72. An ECMcontroller 74 communicates with the data bus 64 via an ECM controllercommunication port 76. In addition, in the illustrated embodiment, anengine retarder 80 communicates with the data bus 64 via an engineretarder controller communication port 82. In one embodiment, theforward vehicle sensor 58 communicates with the data bus 64 via aforward vehicle sensor communication port 84.

As illustrated by the arrow 86, the ACB controller 66 is capable oftransmitting private (proprietary) messages to the data bus 64. Thearrow 90 illustrates that the ACB controller 66 is capable of bothtransmitting and receiving public messages to/from the data bus 64. Thearrow 92 illustrates that the ABS controller 70 is capable of receivingprivate messages from the data bus 64. The arrow 94 illustrates that theABS controller 70 is capable of both transmitting and receiving publicmessages to/from the data bus 64. The arrow 96 illustrates the ECMcontroller 74 is capable of both transmitting and receiving publicmessages to/from the data bus 64. The arrow 100 illustrates the engineretarder controller 80 is capable of both transmitting and receivingpublic messages to/from the data bus 64. The arrow 102 illustrates theforward vehicle sensor 58 is capable of transmitting public messages tothe data bus 64.

With reference to FIGS. 2 and 3, the forward vehicle sensor 58 transmitsa forward vehicle message to the ACB controller 66 via the data bus 64in a step 200. In one embodiment, it is contemplated that the forwardvehicle message is a public message with a transmitter identifier set tothe forward vehicle sensor 58 and a receiver identifier set to the ACBcontroller 66. Therefore, the forward vehicle message is routed from theforward vehicle sensor 58 to the ACB controller 66 via the data bus 64.The forward vehicle message includes information based on a currentrange to a forward vehicle 60.

After the ACB controller 66 receives the forward vehicle message, theACB controller 66 generates a cruise controller message based on rangeand/or relative velocity of the forward vehicle 60 with respect to thevehicle 10.

A determination is made, in a step 202, if an ACB re-broadcast featureis enabled. In one embodiment, the ACB re-broadcast feature is set via aswitch on a dash 32 of the vehicle 10. If the ACB re-broadcast featureis not enabled, control passes to a step 204 in which the ACB controllertransmits the cruise controller message (e.g., a public messageformatted according to the SAE J1939 standard) to the ECM controller 74.In this embodiment, it is contemplated that the cruise controllermessage includes a transmitter identifier set to the ACB controller 66and the receiver identifier set to the ECM controller 74. Therefore, thecruise controller message is routed from the ACB controller 66 to theECM controller 74 via the data bus 64. The cruise controller messageincludes information for adjusting an engine speed and/or torque basedon the current range and/or velocity of the forward vehicle 60. In oneembodiment, the velocity of the forward vehicle 60 is determined basedon previous range measurements between the vehicle 10 and the forwardvehicle 60. Control then returns to the step 200.

If it is determined in the step 202 that the ACB re-broadcast feature isenabled, control passes to a step 206 in which the ACB controller 66transmits the cruise controller message to the ABS controller 70. Inthis embodiment, it is contemplated that the cruise controller messageis a private (proprietary) message that includes a transmitteridentifier set to the ACB controller 66 and the receiver identifier setto the ABS controller 70. Therefore, the cruise controller message isrouted from the ACB controller 66 to the ABS controller 70 via the databus 64. As discussed above, the cruise controller message includesinformation for adjusting a speed and/or torque of the vehicle enginebased on the range and/or velocity of the forward vehicle 60.

Once the ABS controller receives the cruise controller message, aprocessor 110 of the ABS controller 70 determines, in a step 208,whether any additional messages, requesting a change in the enginetorque and/or speed, have been received by the ABS controller 70 from,for example, at least one additional controller 104 on the vehicle 10(see FIG. 1) that communicates with the data bus 64 or generated by theABS controller itself. If it is determined in the step 208 that the ABScontroller 70 has not received any additional messages requesting achange in the engine torque and/or speed, control passes to a step 210for generating an engine control (request) message in the ABS controller70. In one embodiment, the processor 110 of the ABS controller 70generates the engine control request message to include the cruisecontroller message and is formatted as a torque/speed control (TSC1)message. As discussed above, the cruise controller message includesinformation for adjusting a torque, a torque limit, a speed, and/or aspeed limit of the vehicle engine and can include any combination oftorque, torque limit, speed, and/or speed limit.

If it is determined in the step 208 that the ABS controller has receivedat least one additional message requesting a change in the engine torqueand/or speed, control passes to a step 212. In the step 212, anarbitrator 106 determines which one of the messages, received by the ABScontroller, requesting a change in the engine torque and/or speed shouldbe included in the engine control request message generated in the ABScontroller 70. In one embodiment, it is contemplated that the arbitrator106 is included as part of the ABS controller 70.

It is contemplated that each of the messages received by the ABScontroller 70 includes a priority identifier (e.g., low, medium, orhigh). In a step 214, the arbitrator 106 identifies the message havingthe highest priority. If two or more messages are identified by thearbitrator 106 as having the highest priority, the arbitrator selects,for example, the message received by the ABS controller 70 first. If oneof the messages having the highest priority is identified as beingreceived from the ACB controller, in one embodiment the arbitratoridentifies any of the other messages (instead of the message from theACB controller) to be included in the engine control request message. Inanother embodiment, the arbitrator 106 may use other criteria todetermine which engine control request will be included in the enginecontrol request message generated by the ABS controller 70. Thearbitrator 106 may take into consideration any information available,including information available on the data bus. Some examples ofinformation that may be considered by the arbitrator 106 include vehicleyaw, vehicle lateral acceleration, ABS activity, vehicle speed, distanceto the forward vehicle, vehicle steering angle, and vehicle mass. Thearbitrator 106 may also determine a new engine control request based onany of the considered information, its internally generated enginecontrol request, and any additional controllers requesting enginecontrol. Then, in the step 210, the ABS controller 106 generates theengine control request message to include the message identified in thestep 214. In this manner, the arbitrator 106 ensures that when multiplevehicle controllers 66, 104 request a change in engine control, only asingle engine control message is transmitted from the ABS controller 70to the ECM controller 74.

In one embodiment, it is contemplated that the message received by theABS controller 70 from the ACB controller 66 is always identified as alow priority message. Therefore, in this embodiment, messages receivedby the ABS controller 70 from other vehicle controllers 104 that requesta change in engine torque and/or speed will usually have a higherpriority than the message received from the ACB controller 66.

Control then returns to the step 200. The cycle continues until theengine is turned off.

While the present invention has been illustrated by the description ofembodiments thereof, and while the embodiments have been described inconsiderable detail, it is not the intention of the applicants torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. Therefore, the invention, in its broaderaspects, is not limited to the specific details, the representativeapparatus, and illustrative examples shown and described. Accordingly,departures may be made from such details without departing from thespirit or scope of the applicant's general inventive concept.

1. A vehicle control system, comprising: a forward vehicle sensortransmitting a forward vehicle message based on a range to a forwardvehicle; an adaptive cruise controller receiving the forward vehiclemessage from the forward vehicle sensor, the adaptive cruise controllertransmitting a cruise controller message based on the range to theforward vehicle; a braking system controller receiving the cruisecontroller message and transmitting an engine control message based onthe cruise controller message; and an engine controller receiving theengine control message and controlling an engine as a function of theengine control message.
 2. The vehicle control system as set forth inclaim 1, wherein: the range to the forward vehicle is a current range;and the adaptive cruise controller transmits the cruise controllersignal based on the current range to the forward vehicle and a previousrange to the forward vehicle.
 3. The vehicle control system as set forthin claim 1, wherein: wherein the cruise controller message is a privatemessage.
 4. The vehicle control system as set forth in claim 1, wherein:the engine control message includes at least one of a torque controlrequest, a speed control request, a speed limit request, and a torquelimit request.
 5. The vehicle control system as set forth in claim 3,wherein: the engine control message is a public message.
 6. The vehiclecontrol system as set forth in claim 5, wherein: the engine controlmessage includes an identifier indicating the engine control message wastransmitted by the braking system controller.
 7. The vehicle controlsystem as set forth in claim 5, wherein: the public message is a TSC1message.
 8. The vehicle control system as set forth in claim 1, whereinthe braking system controller also receives at least one of anadditional message from an additional controller on the vehicle and thebraking system controller, the braking system controller determining acontrol of the engine is requested to be changed by the at least one ofan additional controller and the braking system controller based on theadditional message, the vehicle control system further including: anarbitrator ensuring only a single engine control message is transmittedfrom the braking system controller when the braking system controllerdetermines a control of the engine is requested to be changed based onmessages from the adaptive cruise controller and at least one of theadditional controller and the braking system controller.
 9. The vehiclecontrol system as set forth in claim 8, wherein: when the braking systemcontroller determines a control of the engine is requested to be changedbased on messages from both the adaptive cruise controller and the atleast one of the additional controller and the braking systemcontroller, the arbitrator determines the braking system controller willtransmit an engine control message based on the additional message. 10.A vehicle adaptive control with braking system, comprising: a data bus;a forward vehicle sensor sensing a distance to a forward vehicle andtransmitting a forward vehicle message, based on the distance, to thedata bus; an adaptive cruise controller receiving the forward vehiclemessage from the data bus, the adaptive cruise controller determining ifat least one of a torque and a speed of the vehicle engine should beadjusted based on the forward vehicle message and transmitting a privatecruise controller message, based on the forward vehicle message, to thedata bus; a braking system controller receiving the private cruisecontroller message from the data bus, the braking system controllerdetermining if the cruise controller message should be included in anengine control message transmitted to the data bus; and an enginecontroller receiving the engine control message and controlling anengine as a function of the engine control message.
 11. The vehicleadaptive control with braking system as set forth in claim 10, wherein:the engine controller does not respond to the private cruise controllermessage.
 12. The vehicle adaptive control with braking system as setforth in claim 11, wherein: the braking system controller receives anadditional message from an additional controller on the vehicle; and thebraking system controller transmits the engine control message, whichincludes one of the cruise controller message and the additionalmessage, to the engine controller via the data bus.
 13. The vehicleadaptive control with braking system as set forth in claim 10, wherein:an arbitrator determines which one of the cruise controller message andthe additional message is included in the engine control message basedon respective priority levels of the cruise controller message and theadditional message.
 14. The vehicle adaptive control with braking systemas set forth in claim 13, wherein: the cruise controller message has alower priority level than the additional message; and the arbitratordetermines the additional message is included in the engine controlmessage.
 15. A method for controlling a vehicle engine, the methodcomprising: detecting a range to a forward vehicle at a forward vehiclesensor; transmitting a forward vehicle message, based on a range to theforward vehicle, from the forward vehicle sensor to a vehiclecommunication data bus; receiving the forward vehicle message at anadaptive cruise controller; transmitting a cruise controller message,based on the range to the forward vehicle, from the adaptive cruisecontroller to the vehicle communication data bus, the cruise controllermessage including a request to change at least one of a torque and aspeed of the engine; receiving the cruise controller message at abraking system controller; transmitting an engine control message, basedon the cruise controller message, from the braking system controller tothe vehicle communication data bus; receiving the engine control messageat an engine controller; and controlling the at least one of the torqueand the speed of the engine as a function of the engine control message.16. The method for controlling a vehicle engine as set forth in claim15, wherein transmitting the forward vehicle message includes:transmitting the cruise controller message as a private message.
 17. Themethod for controlling a vehicle engine as set forth in claim 16,wherein transmitting the engine control message includes: transmittingthe engine control message as a public message.
 18. The method forcontrolling a vehicle engine as set forth in claim 17, whereintransmitting the engine control message includes: transmitting theengine control message with an identifier indicating the torque controlmessage was transmitted by the braking system controller.
 19. The methodfor controlling a vehicle engine as set forth in claim 15, furtherincluding: receiving at least one additional message at the brakingsystem controller from an additional controller on the vehicle, the atleast one additional message including a request to change the at leastone of the torque and the speed of the engine.
 20. The method forcontrolling a vehicle engine as set forth in claim 19, furtherincluding: arbitrating between the cruise controller message request tochange the at least one of the torque and the speed of the engine andthe additional message request to change the at least one of the torqueand the speed of the engine; and including the cruise controller messagehaving an arbitrator selected engine control message transmitted fromthe braking system controller.
 21. A braking system controllercomprising: a communication port receiving messages from a vehiclecommunication system; a processing unit, in data communication with thecommunication port, processing first and second messages requesting tocontrol an engine of the vehicle; and an arbitrator for selecting one ofthe first and second messages to be sent to an engine controller via thevehicle communication system, the processing unit generating an enginecontrol message, including the selected message, to be sent to theengine controller via the communication port.
 22. A braking systemcontroller as in claim 21 wherein: the arbitrator is included as part ofthe braking system controller.